Registered nurse Beth Lenihan from Pacific Trust, who does health checks on pre-schoolers, said the most common problem, regardless of ethnicity, was poor oral health.

"I would say about 60 per cent of the children I see have decay . . . it's something that's often not picked up on and it can get really bad," she said.

Many children had more than one tooth removed because of decay, she said.

Lenihan said parents were becoming "a lot more proactive" about making sure their children received B4 School Checks. The national programme includes a strengths and difficulties questionnaire, and vision, hearing and health tests. It aims to ensure children will reach their potential at school.

Canterbury's performance in B4 checks was called "shambolic" by Health Minister Tony Ryall three years ago.

In 2009 the Canterbury District Health Board (CDHB) delivered the health checks to only 5.4 per cent of eligible children. This year it is on track to hit the 80 per cent Government-set target.

Veniana Naikau and her family have been in New Zealand for three years and her four-year-old son Semi recently received his B4 School Check.

"In Fiji, these sorts of checks just don't happen . . . I really like knowing that he's healthy and he will go to school being happy," she said.

B4 School Checks programme co-ordinator Julie Potter said at the CDHB community and public health meeting this week that Maori and Pacific children as well as those from deprived areas had "two or three times higher referral rates".

"These are our priority children and they have much higher needs than other populations . . . and, unusually, the delivery of checks for these children is higher than for other children, which is really positive," she said.

CDHB member Andrew Dickerson said it was "very commendable" to see such progress being made.

"[It's] a great achievement, particularly given the disruption and dislocation of the earthquakes and the fact that we are targeting the most vulnerable children who can, of course, be the most difficult to reach."